Laurel Electronics LTE: Ethernet & 4-20 mA Output Transmitter for Ratio - Manual

LAUREL ELECTRONICS INC. , 3183-G Airway Ave., Costa Mesa, CA 92626, USA • Tel 714-434-6131 • www.laurels.com 1
LAUREL
ELECTRONICS, INC.
Ethernet & 4-20 mA Output Transmitter for Ratio,
Product, Sum or Difference of 2 Rates or Totals
Features
• Ethernet Serial Data I/O, Modbus TCP or Laurel ASCII protocol
• 4-20 mA or 0-10V transmitter output, 16 bits, jumper selectable, isolated
• Dual 120 mA solid state relays for alarm or control, isolated
• 5V, 10V or 24V dc transducer excitation output, isolated
• Two independently field-scalable pulse input channels A and B
• Arithmetic functions A+B, A-B, AxB, A/B, A/B-1 (draw) applicable to rate or total
• Frequencies from 0.005 Hz to 1 MHz
• Inputs from NPN or PNP proximity switches, contact closures, digital logic,
magnetic pickups down to 12 mV, or AC inputs up to 250 Vac
• Analog output resolution 0.0015% of span (16 bits), accuracy ±0.02% of span
• Universal 85-264 Vac / 90-300 Vdc or 10-48 Vdc / 12-32 Vac power
• Power over Ethernet (PoE) jumper selectable with 10-48 Vdc supply
Description
The Laureate dual pulse input transmitter accepts two inde-
pendently scalable input channels A & B from a wide range of
pulse sources, such as NPN or PNP proximity switches, contact
closures, digital logic, magnetic pickups down to 12 mV, or AC
voltages to 250 Vac. Input frequencies can range from 0.005 Hz
to 1 MHz.
Arithmetic functions A+B, A-B, AxB, A/B or A/B-1 are made
available by the Extended counter main board and can track the
sum, difference, product, ratio, or draw of both input channels.
These functions can be applied to scaled rates, scaled totals,
square root of rates, totals after square root extraction, custom
curve linearized rates, or totals after custom curve linearization.
• Sum A+B can be used to add two flows for total flow, or to
add the number of parts carried by two conveyor belts.
• Difference A-B can be used to subtract outflow from inflow for
net flow, or to subtract reject parts from total parts.
• Product AxB can be used to multiply two rates, for example
to compute horsepower by multiplying torque by RPM.
• Ratio A/B can be used to compare flow rates in two channels,
the RPM of rollers or gears, or the speed of moving machinery
such as conveyor belts. Ratio can also be applied to scaled
totals to compare two batches to be mixed. In this application,
one transmitter is used to monitor the ratio of flow rates, and a
second transmitter to monitor the resulting batch totals.
• Draw A/B-1 is obtained by subtracting 1 from ratio. Draw is
used to measure the elongation of material as it passes
between rollers, or to monitor variation in the speed of rollers
for tensioning.
Exceptional Accuracy and Stability. Laureate pulse input
frequency and rate transmitters determine frequency by taking
the inverse of period as measured with a calibrated quartz crystal
time base. Extremely accurate 6-digit internal readings (±999,999
counts) are processed in software.
The update rate of the transmitter output is a programmed gate
time + 30 ms + 0-2 signal periods. For pulse rates of 60 Hz and
above, the update rate would be 20 per second. Such fast update
rates are ideal for alarm and control.
Standard features of Laureate LTE transmitters include:
• Ethernet I/O, isolated. Supported protocols are Modbus
RTU and ASCII (tunneled via Modbus TCP) and Laurel ASCII.
The latter is simpler than the Modbus protocol and is recom-
mended when all devices are Laureates. Note that RS232 or
RS485 data I/O in lieu of Ethernet is provided by our LT Series
transmitters.
• 4-20 mA, 0-20 mA or 0-10V analog transmitter output,
isolated, jumper-selectable and user scalable. All selections
provide 16-bit (0.0015%) resolution of output span and 0.02%
output accuracy of a reading from -99,999 to +99,999 counts
that is also transmitted digitally. Output isolation from signal
and power grounds eliminates potential ground loop problems.
The supply can drive 20 mA into a 500 ohm (or lower) load for
10V compliance, or 10V into a 5K ohm (or higher) load for
2 mA compliance.
• Dual solid state relays, isolated. Available for local alarm
or control. Rated 120 mA at 130 Vac or 180 Vdc.
• Transducer excitation output, isolated. User selectable
5V@100 mA, 10V@120 mA or 24V@50 mA.
• Universal 85-264 Vac power. Low-voltage 10-48 Vdc or
12-32 Vac power is optional.
Discovery and configuration of Laureate Ethernet Nodes is
easily achieved with Laurel's Node Manager Software, and the
discovered transmitters can then be programmed using Laurel's
Instrument Setup Software. Both softwares run on a PC under
MS Windows and can be downloaded at no charge.